Bovine mastitis is a persistent inflammation of the udder usually caused by bacterial infections. It is generally spread through contact with contaminated milking equipment or other materials. Presently, the only treatment for the disease is through long-acting antibiotics. Milk from cows undergoing mastitis treatment cannot be marketed until the drugs have cleared their systems.
Mastitis has been estimated to cost the US Dairy industry $1.7 B-$2 B/yr. There are two levels of diagnosed disease: (1) clinical mastitis characterized by visual signs of the disease and poor milk quality and (2) subclinical mastitis which is characterized by a high somatic cell count in the milk. The milk from cows showing subclinical mastitis is cultured to detect whether pathogenic bacteria are present. This testing requires that the lab plate the milk and wait a 1-2 days to see whether bacterial strains grow on the plates. Those strains can then be identified by their metabolic reactions or by using PCR-based assays to determine the type of bacteria present. Clinical mastitis causes the greatest financial loss through lowered milk production, so ways of catching the disease early are needed to mitigate the overall loss, and to prevent spread of the disease.
Therefore, there is a need to develop fast and economical mastitis assays.